spal fans are very small in their thickness, they can easily fit. A fan on condenser is a must, you have to get it done else you will not get good results. If space is an issue put a spal fan on the radiator as well and make space for fan on condenser. I repeat you will be sorry and not like the results if there is no fan on the condenser.
Remember, the more the heat condenser sheds, the more the heat the evaporator will absorb. So even if you have to fight with the ac techs of the whole world but do put a very high speed spal or bosch fan on the condenser.
Also search for Xulfiqar's posts, he mentioned something about odd position of compressor in mehran. He suggested something about relocating it to the front for better head dissipation. If you can do that, do that as well.