AshUK you asked a good question, in my case they could (or did) not get it all the 'dip' gunk out. Plus mine slow oozed out over time (months) like a syrup which required multiple cleanups and it definaely eats thru paint/primer/contact, even POR's. Luckly the gunk ooze was only on inside and underneath areas primarialy, the lower rockers seam quick oozing after about a week or two. Thought I would add dip $ spent was around $1800 20 years ago, media blasting in 2019 around $2200 (stripped shells, doors, hood, trunk, hardtopboth top and underside of shell). My sugestion would be to find a dip solution that can both wash and then fully dunk/soak shell in a cleaning vat that would neutralize inside and out (mine was just washed off) - I don't think a hose wash is good enough. Based on my experience I would blast - cleanup is more definable (especially if you can rotate shell on a rotissere) and overall was not that bad using a good air compressor (with clean/dry filtered air) and one of those long air blower/gun nozzels worked great. Individual parts like a convetible frame when dipped willl fill up the tubs inside with gunk which is a mess BTW (been there, done that). Dipping is less $ and quicker it seems than blasting for small metail parts like suspension stuff for example, when I get them back I usually have to deal with light surface rust because these are dipped/rinsed in large baskets so drying quality/time afterwords is iff but the surface rust is easy to hand wirebrush off and then prime/paint, Also want to add that if you are going to powder coat parts blasting is prefered over dipping big time by my powder coating guy