Technical 51 f2 oil filter and rim question

I'm doing a 51 f2 ford truck at work.It has 8 lug wheels and the owner would like to go with a later model steel wheel to get away from tubes.Can anyone tell me what years I can look at to make the swap?The oil filter question I have is this.The truck has a 226 I'd motor.When I changed the oil the oil canister was half full after draining oil pan.I figures the return hole was clogged so I pulled canister and cleaned it out.I filled canister with brake clean and nothing comes out.Does the little br*** ****** in the base have a check ball so it will only return oil under pressure?I took a tiny still bit and gently pushed down inside this tube and felt no movement.Am I looking at this backwards?If there is a check ball in this tube is it the feed and the ball must move up to let oil in and the return is the hole up high in the center tube.This would explain oil remaining in canister even after draining pan.

 

Go the Ford Truck Enthusiasts website. There is a subforum for '48 - 52 trucks. Join up and post your questions. They are as friendly as HAMBers in my experience.

 

1960s even 70s F250 wheels should work out fine. 1966 and older and you can run the F2 caps.
The oil filtration is a p***ive system on these, meaning it is auxiliary and not direct filtration like you see on more modern engines.....Y blocks on up.
The canister did not drain on my 52 Chevy Coupe so I dipped it out with a s**** and wiped it out with a rag.
Some schematics on different makes show a check valve at the oil pump.

 

There is a check ball in the br*** fitting that goes up not down so now it makes sense.Didn't want to pull that fitting without a bit more info.Its threaded in not pressed.Thank you for your help.

 

I'll check them out.Thank you very much.