Thanks for the update on FIL. It's great to see him again. Hope he had a great birthday.
Glad to here that you are still having fun with bikes as well.
HAPPY 91st BIRTHDAY FIL!!!!
It looks like the 62 Strato Flite tank is the same as the Fleetline tank except the red/chrome color scheme is reversed.
Physically, they should be the same tank and should fit on the frame just fine.
Looks like your chrome version is the Fleetline
Page-3 with an illustration of the most deluxe bike in the 1962 line, The Fleetline model U-70. The specifications are given in detail.
Good reference pics here
https://thecabe.com/forum/threads/western-flyer-strato-flyer-headlight-and-tail-light.160568/
@jd56 may have some knowledge on these.