diff --git a/InvenTree/templates/js/translated/forms.js b/InvenTree/templates/js/translated/forms.js
index 1bfe196286..db2c8e46cc 100644
--- a/InvenTree/templates/js/translated/forms.js
+++ b/InvenTree/templates/js/translated/forms.js
@@ -1426,6 +1426,11 @@ function initializeRelatedField(field, fields, options) {
                 data = item.element.instance;
             }
 
+            // Run optional callback function
+            if (field.onSelect && data) {
+                field.onSelect(data, field, options);
+            }
+
             if (!data.pk) {
                 return field.placeholder || '';
             }
diff --git a/InvenTree/templates/js/translated/order.js b/InvenTree/templates/js/translated/order.js
index 93445afea8..dfac640fee 100644
--- a/InvenTree/templates/js/translated/order.js
+++ b/InvenTree/templates/js/translated/order.js
@@ -1661,7 +1661,23 @@ function loadSalesOrderLineItemTable(table, options={}) {
                         in_stock: true,
                         part: line_item.part,
                         exclude_so_allocation: options.order,
-                    } 
+                    },
+                    auto_fill: true,
+                    onSelect: function(data, field, opts) {
+                        // Quantity available from this stock item
+
+                        if (!("quantity" in data)) {
+                            return;
+                        }
+
+                        // Calculate the available quantity
+                        var available = Math.max((data.quantity || 0) - (data.allocated || 0), 0);
+
+                        // Maximum amount that we need
+                        var desired = Math.min(available, remaining);
+
+                        updateFieldValue('quantity', desired, {}, opts);
+                    }
                 },
                 quantity: {
                     value: remaining,
@@ -1760,7 +1776,7 @@ function loadSalesOrderLineItemTable(table, options={}) {
         showFooter: true,
         uniqueId: 'pk',
         detailView: show_detail,
-        detailViewByClick: show_detail,
+        detailViewByClick: false,
         detailFilter: function(index, row) {
             if (pending) {
                 // Order is pending