engine smokes now jdm swap

i just bought a 91 legend for 1800!! yeah i gotta good deal but it smokes a bit on acceleration. i have called around and it would cost me around 1400 to get gaskets and seals changed. i recently found a jdm legend motor and i want to swap it out. it would be cheaper for me to swap engines than to get the older one repaired. besides the engine what other mods do i need to get that engine into my car. i still kinda want to repair my current engine... could i have a friend that knows hondas extremely well help me change the seals and gaskets? how hard is it and what should i be careful about....I love my legend and would hate to hurt it... i made a good purchase and want to keep it... please help