.....will be told here to show that you can use either the 90-degree or the angled spin-on filter adapter on the early '55 -'60 blocks.
The blue filter adapter is the 90-degree one used on B-body big Pontiacs and first-gen '67 -'69 F-body Firebirds. The angled filter adapter is used on all A-body GTO/Le Mans/Tempest and second-gen '70 -'81 F-body Firebirds.
Note that the 90-degree adapter has the oil sender coming straight out the side, while the angled adapter has it coming out towards the rear.
The angled adapter is shown here installed on the '59 block.
As you can see here it's a very close fit.
Same shot, but this time with the stick shift bellhousing in place. As you can see there's plenty of clearance between the filter and the bellhousing.
The only point of interference was the head of this bolt, if there is a lock washer underneath it it hits the filter. The answer is to either go without the washer or shave down the head of the bolt a little.
Here's the 90-degree adapter installed, there's tons of room between it and the engine block.
Side view of 90-degree adapter.
Side view of the angled adapter.
