IMHO you'll miss the better driving abilities of the 914 with any engine, over the Opel GT, having driven both - my 73 2L & one of my old 1970's GF's Dad's GT at the same time... err, back to back all the time.
While I love the "mini-Vette" Opel & my 1st car was a base 1.1L Opel Kadett Notchback Coupe, I'd rate the 914 much better driving car, better investment, etc.
So unless your 914-subie project is a basketcase, you may want to rethink this sale before it goes to the classifieds! Otherwise, I predict a return to the 914s at a later date - whether as an addition to this GT tantelizing you or replacing it!
Cheers!
Tom
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