170 for 225 SWAP - '62 VALIANT

I really wouln't worry about it. It will probably be hard to find a pre 66 engine in good enough condition to just drop in. Also even if the engine is pre 66, I'm pretty sure, it must be from an "A" body, to have the correct oil pan and pickup. It is no big deal to swap the neccessary pieces. The only place you can't just swap parts from your old engine, is where connecting the trans.You must use the flexplate from the later engine, and the adapter bushing I mentioned. That's it. If you get a late engine with no flex plate, it will be no problem to get one. They are available new or used (I have some used, as would others on this site). The adapter bushing is available from several sources, TFPatty, Doctor Dodge, or myself (I sell them for $20 shipping included).