Any shogun guru’s here?

[Goreden]

Hi all, been a while since i’ve been on here but need some advice on a 3.2 diesel shogun that i might be looking to buy cheap
Basically it needs some work, rear brakes (no worries)
Mot (again no real worries)
The big one for me is it’s hard to start and lacking a bit of power, now i’ve read horror stories about the injection pump
Question is are they really that bad and how hard are they to sort out?
Now i don’t know it is the pump but i don’t know it isn’t either
Any advice greatly appreciated
Cheers in advance