Sorry, but the 2002-2004 Boxster S engine was a 3.2L, not a 3.6L. later models got a 3.4L engine, but there were no 3.6L M96/97 Boxsters from the factory, although there was a 3.8L 9A1 engine in 2015-2016 "Spyder" model. You can interchange 3.2 and 3.4 cylinder heads within certain bounds and caveats: Both engines need to have the same cam drive systems (chain styles and number of chains varied over model years).
986
1997–1999 2.5 L (2,480 cc) 204 PS (150 kW; 201 bhp) 245 N⋅m (181 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six "M96.20"
2000–2002 2.7 L (2,687 cc) 220 PS (162 kW; 217 bhp) 260 N⋅m (190 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam) "M96.22"
2003–2004 2.7 L (2,687 cc) 228 PS (168 kW; 225 bhp) 260 N⋅m (190 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "M96.23"
2000–2002 3.2 L (3,179 cc) 252 PS (185 kW; 249 bhp) 305 N⋅m (225 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam) "M96.21" (Boxster S)
2003–2004 3.2 L (3,179 cc) 260 PS (191 kW; 256 bhp) 310 N⋅m (230 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "M96.24" (Boxster S)
2004 3.2 L (3,179 cc) 265 PS (195 kW; 261 bhp) 310 N⋅m (230 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "M96.24" (Boxster S "50 Jahre 550 Spyder")
VEHICLE ENGINE TYPE MY ENGINE NO. TECHNICAL DATA [2]
BOXSTER M96.20 97 V 65V 00501>60000 6ZYL/2,5L /150 KW
BOXSTER M96.20 98 W 65W 00501>60000 6ZYL/2,5L /150 KW
BOXSTER M96.20 99 X 65X 00501>60000 6ZYL/2,5L /150 KW
BOXSTER M96.22 00 Y 65Y 00501>60000 6ZYL/2,7L /160 KW
BOXSTER M96.22 01 1 651 00501>60000 6ZYL/2,7L /162 KW
BOXSTER M96.22 02 2 652 00501>60000 6ZYL/2,7L /162 KW
BOXSTER M96.23 03 3 653 00501>60000 6ZYL/2,7L /168 KW
BOXSTER M96.23 04 4 654 00501>60000 6ZYL/2,7L /168 KW
BOXSTER "S" M96.21 00 Y 67Y 00501>60000 6ZYL/3,2L /185 KW
BOXSTER "S" M96.21 01 1 671 00501>60000 6ZYL/3,2L /185 KW
BOXSTER "S" M96.21 02 2 672 00501>60000 6ZYL/3,2L /185 KW
BOXSTER "S" M96.24 03 3 673 00501>60000 6ZYL/3,2L /191 KW
BOXSTER "S" M96.24 04 4 674 00501>60000 6ZYL/3,2L /191 KW
987
2004–2006 2.7 L (2,687 cc) 240 PS (177 kW; 237 bhp) 270 N⋅m (200 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam) "M96.25"
2006–2008 2.7 L (2,687 cc) 245 PS (180 kW; 242 bhp) 273 N⋅m (201 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "M97.20"
2004–2006 3.2 L (3,179 cc) 280 PS (206 kW; 276 bhp) 320 N⋅m (240 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "M96.26" (Boxster S)
2006–2009 3.4 L (3,387 cc) 295 PS (217 kW; 291 bhp) 340 N⋅m (250 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "M97.21" (Boxster S)
2007–2008 3.4 L (3,387 cc) 303 PS (223 kW; 299 bhp) 340 N⋅m (250 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "M97.22" (Boxster "RS 60 Spyder Edition", Boxster S "Porsche Design Edition 2")
VEHICLE ENGINE TYPE MY ENGINE NO. TECHNICAL DATA [3]
BOXSTER M96.25 05 5 615 00501>60000 6ZYL/2,7L /176 KW
BOXSTER M96.25 06 6 616 00501>60000 6ZYL/2,7L /176 KW
BOXSTER M97.20 07 7 657 00501>60000 6ZYL/2,7L /180 KW
BOXSTER M97.20 08 8 658 00501>60000 6ZYL/2,7L /180 KW
BOXSTER "S" M96.26 05 5 625 00501>60000 6ZYL/3,2L /206 KW
BOXSTER "S" M96.26 06 6 626 00501>60000 6ZYL/3,2L /206 KW
BOXSTER "S" M97.21 07 7 677 00501>60000 6ZYL/3,4L /217 KW
BOXSTER "S" M97.21 08 8 678 00501>60000 6ZYL/3,4L /217 KW
BOXSTER "S" RS SPYDER M97.22 08 8 668 00501>60000 6ZYL/3,4L /223 KW
987 II
2009–2012 2.9 L (2,893 cc) 255 PS (188 kW; 252 bhp) 290 N⋅m (210 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "MA1.20"
2009–2012 3.4 L (3,436 cc) 310 PS (228 kW; 306 bhp) 360 N⋅m (270 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "MA1.21" (Boxster S)
2010–2011 3.4 L (3,436 cc) 320 PS (235 kW; 316 bhp) 370 N⋅m (270 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "MA1.22" (Boxster Spyder)
VEHICLE ENGINE TYPE MY ENGINE NO. TECHNICAL DATA [4]
BOXSTER MA1.20 09 9 __9 00501>99999 6ZYL/2,9L /188 KW
BOXSTER MA1.20 10 A __A 00501>99999 6ZYL/2,9L /188 KW
BOXSTER MA1.20 11 B __B 00501>60000 6ZYL/2,9L /188 KW
BOXSTER MA1.20 12 C __C 00501>60000 6ZYL/2,9L /188 KW
BOXSTER "S" MA1.21 09 9 __9 00501>99999 6ZYL/3,4L /228 KW
BOXSTER "S" MA1.21 10 A __A 00501>99999 6ZYL/3,4L /228 KW
BOXSTER "S" MA1.21 11 B __B 00501>60000 6ZYL/3,4L /228 KW
BOXSTER "S" MA1.21 12 C __C 00501>60000 6ZYL/3,4L /228 KW
BOXSTER SPYDER MA1.21 11 B C_B 50501>60000 6ZYL/3,4L /235 KW
BOXSTER SPYDER MA1.21 12 C C_C 50501>60000 6ZYL/3,4L /235 KW
981
2012–2014 2.7 L (2,706 cc) 265 PS (195 kW; 261 bhp) 280 N⋅m (210 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "MA1.22"
2014–2016 3.4 L (3,436 cc) 315 PS (232 kW; 311 bhp) 360 N⋅m (270 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "MA1.23" (Boxster S)
2014–2016 3.4 L (3,436 cc) 330 PS (243 kW; 325 bhp) 370 N⋅m (270 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "MA1.23" (Boxster GTS)
2015–2016 3.8 L (3,800 cc) 375 PS (276 kW; 370 bhp) 420 N⋅m (310 lbf⋅ft) water-cooled DOHC 24-valve Boxer flat-six (VarioCam Plus) "MA1.24" (Boxster Spyder)
VEHICLE ENGINE TYPE MY ENGINE NO. TECHNICAL DATA [5]
BOXSTER MA1.22 12 C __C 00501>60000 6ZYL/2,7L /195 KW
BOXSTER MA1.22 13 D __D 00501>60000 6ZYL/2,7L /195 KW
BOXSTER MA1.22 14 E __E 00501>60000 6ZYL/2,7L /195 KW
BOXSTER MA1.22 15 F __F 00501>60000 6ZYL/2,7L /195 KW
BOXSTER MA1.22 16 G __G 00501>60000 6ZYL/2,7L /195 KW
BOXSTER "S" MA1.23 12 C __C 00501>60000 6ZYL/3,4L /232 KW
BOXSTER "S" MA1.23 13 D __D 00501>60000 6ZYL/3,4L /232 KW
BOXSTER "S" MA1.23 14 E __E 00501>60000 6ZYL/3,4L /232 KW
BOXSTER "S" MA1.23 15 F __F 00501>60000 6ZYL/3,4L /232 KW
BOXSTER "S" MA1.23 16 G __G 00501>60000 6ZYL/3,4L /232 KW
BOXSTER SPYDER MDB.XA 16 G DBX 00501>60000 6ZYL/3,8L /276 KW