advice WRT Suzuki Engine

[carryman88]

ok ppl.....so had a minor misfortunate incident n my dad borroed the van n by accident put diesel in the gas tank....
since that the mech has flushed out the tan n stuff but i am gettin some serious power problems n was wondering if it had n e thing to do with the diesel......n well it shut down on me last week n teh mech doesnt kno wat 2 make of it....
now the van is in rpetty good conditionbody wise so i was thinkin i could take this oportunity to do an engine swap....now wher eu guys come in on d advice...
if i am to swa and engine the engine that i have in mind is the 1.3 suzuki jimny engines M13A for 3 main reasons
1. Powerful
2. RWD
3. it's a 1.3 similar 2 d one i hve in it now

the question now comes about with how hard wud it be to do a transpalnt like this.....my biggest problem is d gear box...because of how it is built up in d carry ure basically sittin on d engine.....n changing d gearboc wud mean u have 2 find a way 2 redo te mechanism with respect to the shifter......i was wondering if the gearbox i have on the G13BB (current engine) wud fit onto the M13A engine

if any one can render n e assistance this would be greatly appreciated

thanks alot
CARRYMAN!