Oh your 1999? Well a p-pump swap is doable but not a piece of cake. The p-pump, when properly modded will flow more fuel then a VP44. But stock I think the vp44 might have the edge.
I am not a fan of the vp44 so I would say do the swap. Yes it is alot of work, need new front gear train off of 12v, most likely the cam of the 12v depending if you want electric or machincal lift pump, new injector lines, oil feed line for injection pump etc.
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