[Vwdiesel] Can 91 VW Jetta Engine with TDI be put in 88 gassy?

[Jim Kvarnberg]

My 91 VW Jetta TDI failed insurance inspection because of severe 
structural rust problem along the right side.  I have a good gassy 88 VW 
Jetta, but its automatic transmission is shot.  The 91 Jetta has five 
speed transmission.  Here is what I am thinking ... pull the gas engine 
with tranny out of the 88 and the engine TDI with manual tranny out of 
the 91 to put it in the 88.  May I hear your feedback or, if any, 
instruction/suggestions on this?  Is this idea feasible?  Thank you in 
advance.  Jim