Swapping a series II in isn't really that hard. Pull the axles out of the car, undo the wiring harness and radiator hoses and fuel lines and downpipe. Pull out engine and tranny. Drop in new engine and tranny, put axles in, install new wiring harness and PCM, splice wires, radiator hoses, exhaust, and a few other things I'm sure I forgot to mention. You'll also have to add the OBDII diagnostic port under the dash in place of the OBDI port, but thats obviously not a big deal.
Its really not that hard and can easily be done in a weekend. The hardest part is splicing the wires, get FSM'* from the car your putting the engine in and the car the harness came from and you're all set.
Not saying whether you should do it or not, just that its not as hard as some people make it out to be.
Just my $.02.
1990 Maroon Grand Prix STE McLaren 3.1 Intercooled Turbo, 14.695 @ 94.49 on 12psi before cam/heads/etc.
1990 Bright Red Grand Prix McLaren 3.1 Intercooled Turbo, 14.819 @ 92.72, 189whp
1999 Grand Prix GT 9.75:1|K&N|160 tstat|No Ubend/Cat/Res|UD Pulleys|Ported M90/TB/Heads|XPZ|2.55"|Pacesetters|Stage 2 I/C. 12.442 @ 112.78
2000 Blue Bonneville SSEi Supercharged Gutted Airbox|K&N|3.4"|1.9'*|WP Pulley|Custom DHP|180*stat|41932'*|No Cat. 14.681 @ 94.80
2002 Dark Cherry Grand Prix GTP Supercharged & Intercooled
12.084 @ 114.38 w/1.743 60', 315.6whp, Fastest Stock Cam M90 GTP!
NOW XP CAMMED, 340.6whp with XP, stock heads, Gen 3 M90, 11.984 @ 115.84 w/1.750 60'!
Most HP Stock Heads Gen 3 M90 GTP!
2004 Red Monte SS Supercharged K&N|3.4 Pulley|1.9'*|180*stat|41919 plugs|3" dp|No cat/ubend|DHP|Shift Kit. 14.2 @ 98
GOT BOOST??? Friends dont let friends drive stock!