Steps for Upgrade to PI 7.4 Dual Stack from PI 7.01

Hello Experts,

We are planning to upgrade our SAP PI 7.01 system to SAP PI 7.4 Dual Stack. We have already gone through the SAP Netweaver 7.4 Upgrade Master Guide, and have done the following:

1. Creation of Maintenance Transaction in SOLMAN MOPz
2. Stack file generation
3. Download of Upgrade Media as dictated by the Stack File
4. Download of SUM SP14

Where our question lies is about the next steps. As per the upgrade master guide, we need to split the dual stack, and move into a single stack installation. However, our decision is to continue with dual-stack in 7.4. And dual-stack is supported in PI 7.4 as exception, as per the master guide. So, the first question is: do we really need to split dual-stack for PI?

The second question: what are the next actionable steps? As per the upgrade guide, we have to now:

1. Upgrade the NW for Product Instance PI.
2. Upgrade of Adapter Engine
3. Perform delta configurations

Will this upgrade both ABAP and Java AS Instances? The upgrade guide suggests that from our source release (7.01) to target release (7.4), we need to follow upgrade procedure for Java, and EHP installation procedure for ABAP. Will this be done in the SUM tool itself?

Please provide guidance.

Thanks in anticipation!