The 250 is great upgrade for the 194. Even in a stock configuration it will greatly improve the performance of your Chevy II. Paint it Chev orange, throw on a couple of factory 194 decals on it and no one will know the difference. If want to be totally stealth, make sure you get a 250 without the emissions holes in the head or use your 194 head. You will likely want to use the stock pan and pick-up from your 194 unless you luck out and find a 67 Chevy II 250.
No need to worry about sub-framing it with a mild 250l; it will hold up fine. The stock drive train will also hold up if you drive it somewhat conservatively. Nothing wrong with it, but it is 40+ old technology. If you plan on driving it hard, it may be worth while finding a 10 bolt rear from a 64-67 and adding front disk brakes. This will require going to 5 bolt wheels, but if you have 14" wheels now, you can use your stock wheel covers to continue the totally stock look.
Good luck with your Inline II
