The switch does come pre-adjusted.
The big problem with your A/C is the excessive pressure. Sounds like somebody dumped in a couple cans of refrigerant. Might even have air in it.
Most common reasons for excessive high side:
1) Too much refrigerant
2) Air in system
3) Too much oil
4) No air flow across condenser
5) Restricted condenser
Since you just bought the truck, my money is on "too much refrigerant".
A little bit of oil and dye is pushed out by the refrigerant whenever a switch is replaced. No worry. The pressures given do NOT suggest an orifice tube problem.
The environmentally correct way of dealing with an overcharged A/C is to have the excess recovered by a technician certified to handle refrigerants, using an approved machine. You may only need 8-10oz recovered from the system. It's just a guess.
However, the text-book correct way to deal with this situation is to recover, evacuate, recharge.
P.S. Thanks for providing gauge readings! It makes a huge difference.
You can order a factory repair manual from Helm:
https://www.helminc.com/helm/Dealer....XTHT5K9D7U43G3