how interchangeable are 80 kz550/81 kz750 parts?

i have an 81 kz750... my ignition is aftermarket... and none of the local locksmiths can duplicate my ONLY key (bull shit i know)... soooo i'm looking for a replacement so my key will work in everything...

my question is... will an 80 550 ignition work in my 81 750??

someone told me that the gas cap doesn't really even need a key... haven't tested the theory but... i'd still like to have everything match...

and i don't have a seat lock (need one and i found a set that has everything)....

current key is #368... the letters on the key are "Qinf" or the "Q" might be Q or might be a logo... i can't tell...

help anyone??

Rstnick is a member here and should be able to help you. He is a wiz with locks. He'll probably chime in.

actually i solved my problem... i quit going through dealers and did work myself at a "do it best" store... my aftermarket ignition is from EMGO... EMGO does not offer replacement blank keys.... soooooooo i actually matched my EMGO ignition key to a nissan car key... and IT WORKS!!!!... couldn't believe it... $3 for a replacement key... everyone has been telling me that i'll actually have to get a new ignition set for $42 (emgo) or $120 (stock)... amazing... thanksfor the reply though...