Slant six single, to slant six double.

I vote leave it 100% stock, tune it up real good and drive it. When you’re ready for more power, toss it in the can and put a small block in it. Don’t waste a single dollar modifying or upgrading a slant as most I’ve talked to that have done it end up unsatisfied and swap em anyway.
Fire away slant6ophiles.
Of course I've thought about it. Just seems like throwing a 318 in it is alot more work. From the suspension to a different trans. Just alot haha