88 Chevy pickup possible fuel problem?

[WestButteTruck]

I will add another issue. I took the bed off the truck and quit for the evening. That next morning was a strong gas smell in the garage. Wife thought the cat died from breathing gas fumes all night.....I could only wish. Anyway....I went over to investigate further and found gas bubbling out of the top of the sending unit. It was coming from the base of the middle tube(corroded?), not sure if this is a return line or what. But gas/air was bubbling out and onto the floor. Another interesting thing was that same line had a bunch of "frost" on the line from the tank back about 8" or so. I cracked the gas cap and let off the pressure and it quit of course. Would the tank still have that much pressure built up inside? What's with the frost? It was 45 deg in my garage. I would have taken a pic, but it's now -20 and the truck is outside. I've already ordered a new sending unit and have a new pump also.