I have a 1969 350 block # 3955582 at least that the year I believe it is. I have been trying to get a set of freeze out plugs, but they are always too large. My side block holes measure approximately 1.48” in diameter. The plugs are way to big to fit. Has anyone else had this problem and if so what did you buy to fit. Thanks for any help.

 

So if the holes measure 1.48" then you likely need a 1.50" diameter plug. Perhaps you have been given 1 5/8" plugs (1.625" diameter) instead?
It takes some force to insert the plugs, typically I use a hammer and a socket or other cylindrical object that's slightly smaller diameter than the plug to drive them in.

Here's a link to Rock Auto's web site that shows the expansion plugs for a 1969 350 engine:
https://www.rockauto.com/en/catalog/...sion+plug,5332

 

Did you buy a complete kit, or just individual freeze plugs? I've had no issues with the Pioneer kits.