I really hate to see mismatched rear tires on a tractor, the right side looks like a Firestone tread to me and the left might be taller? The rear wheel weights are nice.
The 135 is not a particularly good tractor for FEL work-front axle is not that strong. The MF-150 is better for that type of work.
Looks like the FEL on this 135 is operated via a front-mounted hydraulic pump. I know that the 135 is supposed to be able to handle this setup. However, the 1st owner of my 1964 135 had this FEL setup and snapped the crankshaft where it passes through the front main bearing. I'd check this out carefully. Operate the FEL. Listen for any strange noises coming from the front of the engine.