Slant six space

When I first got my 64 225 running, I used a new see through gas filter. It never truly filled up enough to eliminate the air bubble. The engine ran perfectly so I just ignored it.

Later, after I started putting miles on it during hot summer days, it started showing symptoms of heat soak. The factory original fuel line had cleaned up nicely and looked brand new. But I removed that and did the SlantSixDan recommended fuel line reroute and used a metal can filter for safety.

Now it runs better than perfect.

Your fender to distributor gap sounds about right. People forget that the early A-bodies have a narrower engine bay than 67 and newer. It may seem tight but compared to modern front wheel drive vehicles, we don't have it so bad.