Thanks mrfixit,

Im going to make an extension hose for my pressure gauge so I can see easier as it warms up.

I did have a problem with the inching lever last year, the spline shaft clamp was not tight & it would not return properly, had to cut widen the clamp gap, fitted a GR8 bolt & it tightened up good. I will look close at this valve operating.

I spoke to transmission rebuilder yesterday & they advised "transmission fix" additive is only good for short term remedy by swelling seals to improve pressure.

I will check & clean the pump screen. (The line filter was pretty cruddy when I checked it (probably the first clean its had in 20 years))

One thing I wonder if ATF is available in heavier viscoscity ?