Lan Process
Well, both Commercial written and Phraseology tests are for the certificate conversion. For those you will need to study what is in the DGAC website. They have those published, and that is exactly what you will have... you also have the option of English or Spanish for the Commercial...
I have found that applying for a job in Peru, while you are in the US is a very expensive process. First, you send your resume. I really do not know if they will call you if you have a foreign address. Most likely they will send you an e-mail asking you to apply and the dates you plan to be in Peru. With that, they might, or might not, have evaluations those weeks. So, before the tickets are bought, make sure you have "una agenda de evaluaciones". For me, all the tests happened in a week. Then again, I was lucky that they had evaluations while I was there, except, I had to extend my stay, and pay the penalties for doing that. I know of people who had started the process and had to wait a week or two before they were asked to go to do an interview or the sim ride.
Sim ride is very basic: attitude control, situation awareness and CRM. You will be flying a B737 simulator (static, but full cockpit) with a co-pilot (who knows the plane). you will do a take-off, turn to the ocean, cleared to LIM VOR for the ILS B or C descent approach and landing. That is it!
Hope that helps.