@Matt1260
I THINK it could be a transition engine released by Toyota between the 1F and the 2F so I've heard it called the "1.5F" I imagine someone (particularly old timers) will object to calling an F engine "1F", but, in my opinion, if WWI ("the war to end all wars") didn't get that moniker until WW2 came along, it makes sense to designate the F engine the 1F.
So, Living says "

it's not a 2F oiling system but a late F engine oiling system improvement that was carried over to the 2F." may be semantics; my point was that just by looking at your picture, your engine has the outer physical appearance of a 2F due to its attributes noted below.
So, if you have an F engine that looks like a 2F, then it's likely a transition engine with the benefit of "a late F engine oiling system improvement that was carried over to the 2F".
My "limited" understanding is that in the early 1970's there was the F engine, and by 1975 or so there was the 2F engine, but some time between Jan 1973 (I have a Jan '73 with a bonafide F engine) and 1975, let's say 1974, there was a transition engine IN SIMPLIFIED TERMS that was part F engine and part 2F engine. (let me clarify: in VERY simplistic terms). So, call it 1.5F or "F.5" but it's not the early 1970's F and it's not a 2F.
The early 1970's F engine mentioned above had partial oil filtration (the oil filter housing was bolted to the manifolds and was supplied with a hose into the filter and then oil returned by hose to the crankcase) and also had a thin copper oil supply tube threaded up through the block and head to a fitting in the middle of the rocker arm tube. The 2F had full filtration of the oil, with the filter housing bolted to the passenger side of the engine, between the distributor and the fuel pump. The dipstick was relocated behind the distributor. the rocker arm copper tube was eliminated because they found a way to feed the oil to the rocker arms through an oil gallery integral with the block, head and boss supporting the rocker arms. Your picture has all those components in the right places to be considered "a late F engine oiling system improvement that was carried over the the 2F".
For the transition engine, which likely has a serial number that starts with "F" and not "2F", some 'Mudders have suggested the engine performance is better than the later 2F, so, with better performance and a much improved oiling system, 1.5F engines have been considered (by some, anyway) to be a desirable upgrade.