I built a 2.5L EJ205/EJ257 hybrid motor for my car. It'll be December before I hope to run the car, but I'm looking for some advice on first start and break in for a modified engine.

I intend to get the car tuned on a dyno, but I'd like to do the first start/troubleshooting and first drive before that happens. However, I have no idea if the tune that was already on the donor will run/idle with the new configuration (Donor was also a hybrid swap, poorly done, but had larger injectors, TGV deletes, different intake, different fuel pump, different turbo, and different pistons than what are now on the car). I also think I might be much too far from stock to run a normal EJ205 tune for this.

Many Subaru threads have said to get a baseline tune via email from your chosen tuner and start off with that. However, I don't have an AccessPort or ECU cable that would allow me to flash it.

Any advice on this? I can purchase an Accessport or PC cable to flash, but I don't want to be throwing money away on something to use once. Any engine break in tips would be appreciated as well.