now there is a distance of 0.492 "

The math for calculating the minimum required distance is as follows:
Lobe lift multipled by the rocker ratio plus 0.060” minus the valve lash.
 
In your case: 0.320” X 1.43 + 0.060” – 0.020” = 0.498” minimum
 
If going with 1.6:1 rockers then: 0.320” X 1.6 + 0.060” – 0.020” = 0.552” minimum
 
More than minimum is always desirable.

Lorena, Texas (South of Waco)

Thanks Ted, good explanation, I will try to go to the maximum possible space

After adapting the valve guides, I am looking for new seals, they have to be 11/32 "x 0.500". Any suggestions for this?
I have these two visits:
ENGINETECH S2926
QUALCAST 3881045

For positive type valve seals, I use U.S.Seals Inc.  For the 11/32” X 0.500” applications the part number is VS107V.
 
https://ussealparts.com/catalogsearch/result/?q=vs107v 

Lorena, Texas (South of Waco)

Thanks Ted 👍

I screwed up, I hadn't measured accurately enough, it should be 11/32 "x 0.510". I'm sorry

I only see .500 "-.502" -. 530 ", could anyone fit in?

The VS107V seal is rubber lined on its inside and doing a rough measurement with a dial caliper on my end indicates that it may work on the 0.510” diameter guide.  This may just require some oil on the guide and seal surfaces to help the seal slide in place.  Here’s a picture of the seal dimensions page from the U.S. Seal catalog which may help you make a more informed decision if you want to use the #107 seal or possibly another.
  

Lorena, Texas (South of Waco)

Ted thanks for the information, I'm going to order a VS-107V game. I can have them in oil some time before. Looking at U.S. SEAL, I have seen this other seal, I can order both and see what happens.

https://ussealparts.com/vs-vo3v.html