Notorious Lifter/Pushrod ticking?

[Fordtoughranger]

My 91 4.0L has seemed to had the noisy valvetrain issue since I bought it about 2yrs ago, but it was so slight that I thought at the time it was an exhaust leak. Then beginning of this winter the noise got more noticeable, and I have just let it be and turn the radio up. Then a few weeks back my aftermarket mechanical oil pressure guage dropped from usually reading 60psi to reading the stated minimum of 40psi at 2000rpm and the noise has become really noticeable at startup at about 50deg weather. In the last two days the cold start starts and then there is a rough idle for a few minutes. Then today after work I went to start it and it was hesitant to turnover. With a little bit of cranking and stutters it started and idled rough for a few minutes then went to its normal routine. Once it gets warmed up to about 180deg it is a lot less noticeable. Then at idle when warm it usually can be heard with a 2second interval.
I did give in this morning and poured in some seafoam, and 2ea 30min trips hasn't changed anything.

Does this sound like the usual valvetrain issues with the hard starts and lower oil pressure?
I know the pushrods are big problem in the 4.0L and the lifters are common in the 2.9L, but it could be the lifters in the 4.0L as well?

Any ideas and advice would be appreciatted!
Thanks