Been there, done that, got the t-shirt - welcome to the club.
All suggestions above will work, it may even require various combinations.
I had such a problem with the front lock bolt on my first build, that I ended up pluging the stock holes with dowels, the lock plate with a bolt, and filed all smooth. Then I tapered the ram rod, and reduced the front lock bolt to a 6-32. Between the relocated hole, skinnier ramrod and smaller diameter bolt, I finally got the clearence needed. I'm sure there was a simpler way, but that's the road I took.
It's been said in this forum before . . . the difference between good and great is not the mistake, but how it's corrected.