When signing the pact of steel with hitler, Mussolini originally planned for a 4 year period to prepare for war with the other great powers of Europe... And he only joined sooner because Germany was successful and he didn't want the Germans to take everything for themselves. In this scenario, Mussolini had already prepared his army for a modern war by 1938.
The main question is, what would be the best way for Mussolini to navigate his way through the tense political and military situation of europe. Italy is aiming to get a seat on the un security council, keep its great power status, and to get a a it's own portion of Germany like France, the uk, the us, and the ussr did.