are the hard parts available to get it up & running? reciever/drier & the valve on the firewall etc. Not opposed to converting to R134 if recommended. can a person rent the gauges/hoses/vac pump & do it at home? tho it would be my first time with this. I have my eye on one & I think the A/C is non op & A/C is pretty much a dealbreaker for me. thank you for your time