KEEP IT SIMPLE!
fuel starvation + new fuel pump = 1.blocked supply line
2.defective pump (unlikely)
Back blow the line. Disconnect supply line abaft the fuel pump, blow air rearward to the tank.
DO NOT BLOW AIR THROUHG THE FUEL PUMP!
If this fixes the problem it may only be temporary. Gunk in the tankl can haunt you for years. If sympoms persit or for peace of mind. Drain the tank. The small steel supply line can clog easily, and if there is corrosion in there the rust from the tank will give you a partial blockage. For the record I had this problem and did not need to replace the line, just had to get all the smutz out of the tank (weird stuff that looked like bits of astro turf).
Forums are great places to get info and ideas one hasn't thought of, but trouble shooting requires a very systematic train of thought. Each step should reduce variables from the most obvious first to the more esoteric (water in gas boiling creating vapours that back blow the supply!) later.
So good luck with that, Patrick
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Patrick, '68 220, '92 Eurovan (work truck).